1. Field of the Invention
The present invention relates to a technique for enabling communications between a communication device that performs an intermittent reception operation and a communication device that performs a continuous reception operation.
2. Description of the Art
Patent Document 1 (JP-A-2003-87180) discloses a communication system that enables a receiving station to perform an intermittent reception operation in an irregular transmission radio system having no radio station that regularly transmits a control signal. To be more specific, in a radio communication system comprising a calling station and a called station, the called station in a reception waiting state brings the reception portion into an operating state intermittently for only a time d at a specific cycle (d+t). Meanwhile, the calling station that is to start communications by calling up the reception-waiting called station transmits a reception portion activation signal for a period longer than the cycle (d+t) before it transmits the call number of the called station. Because the reception portion of the called station is brought into an operating state for the time d at the cycle (d+t), the called station is able to trap the activation signal longer than the cycle in a reliable manner and thereby brings the reception portion in a continuous operating state.